On Android 4.4 KitKat you can set the Status and Navigation bars transparent with the android:windowTranslucentStatus and android:windowTranslucentNavigat
Set android:windowTranslucentStatus to false and set android:statusBarColor to @android:color/transparent.
Then add code below:
getWindow().getDecorView().setSystemUiVisibility(
View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN);
If you also want the navigation bar to be translucent, set android:navigationBarColor to @android:color/transparent and combine the flag View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION as well.
I didn't experiment on the navigation bar but it will work.